Induction heating head



H. E. SOMES INDUCTION HEATING HEAD seepf. 26, 1944.

Original Filed Oct. 18,- 1941 NVENTOR Howard E. Sox/nes ATTORNEYPatented Sept. 26, 1944 OFFICE INDUCTION HATING HEAD Howard E. Somes,Detroit, Mich., assigner to Budd Induction Heating, Inc., Philadelphia,Pa.. a corporation of Michigan original application october, 1s, 1941,serial No.- 415,580. Divided and this application June 11,

\ 1942, serial No. 446,568

(Cl. 21S- 13) 9 Claims.

'I'his application is a division of my application E Serial N0. 415,580,led October 18, 1941.

This invention relates to apparatus for heat treating metal eproductsand particularly to an induction heating .head for use in suchtreatment.

An object is to provide an induction heating head especially constructedand arranged for horizontal operation in heating the inner sur- 'facesof hollow workpieces, although it will be apparent that the' inventionincludes features adapted to either vertical or horizontal work.

A further object is to provide an induction heating head constructed andarranged to per-l mit the heating coil being quickly removed from asupporting arbor and replaced by a coil of different size.

A further object is to provide an induction heating head `constructedand arranged to convey coolant to and from the heating coil withoutdischarging any`of the coolant fluid outside of the head.

These and other objects which will be apparent are attained by thepresent invention which is Villustrated in the accompanying drawing, inwhich Figure 1 is a longitudinal sectional view` upon the end of themandrel. lThermal insulating means is provided between the separatepassages to prevent the temperature of the coolant owing to the coilbeing raised'by the heated iiuid which has passed through the heatingcoil and is being conveyed away therefrom.

The illustrated embodiment shows an inducing conductor l0 having anumber of convolutions and provided with an inner passage Il torcooling. Water or other appropriate coolant is supplied through thepassage I 2 in the hollow arbor, thence through passages I3 and I4 to aradial passage I3, through the several turns of the inducing conductorand thence through a radial hollow connector plug Il. From the plug Ilthe coolant. ilowsv through a slot I3, radial 55 the end of the tube 31.

bore I6' and chamber Il formed in an end plug I 8, and back throughinner heat insulated passages |3 and 20.' The passage for conveying thecoolant away from the heating coil is thermally insulated. Radiallamlnations 2| enclose the inducing conductor as is well known in theart, and these laminations are mounted on an annular coil support 22having an annular extension 23 engaging electrical contacts formed bycircumferentially spaced, yieldable` ngers 24 contacting an outersurface 25 of reduced diameter on the inner end of such extension 23 andconnected to an inner annular arbor portion 23. r'l'he other end of theconductor coil is electrically connected through the insulated, hollowconnector 21 with an insulated arbor member 28.

In order to permit ready replacement of one head with another ofdifferent diameter, to accommodate diierent sizes of workfpieces, thepresent invention provides a construction per mitting such change uponremoving two threaded connections. The coil support 22 is secured inplace by. an 'elongated hollow bolt 29 having a head 30 engaging in andclosing the end of a hollow sleeve 3l, and an inner end threaded to thereduced bore of an annular arbor member 32 which is in turn threaded tothe insulated arbor portion 28. The inner end of the sleeve 3l slidablyengages the bore of the arbor member 32. The greater portion of theelongated bolt 29 is of somewhat reduced diameter to provide for thecoolant conveying passage I4. The

coolant conveying passage I9 formed within the a substantial distancetherethrough. The insu-v lating member has a head 35 bearing againstouter end of .the bolt and expanded over y e head of a retaining ring 36keyed to the inner annular end of the chambered plug I8 which isrotatable relatively to the ring so that rotation of the plug will'haveno twisting effect upon the head 35 of the insulating member 34. Thecentral coolant passageway 20 is formed by a hollow member 3l connectedto the annular arbor member 32 by a hollow connector 38 threaded intothe arbor member and frictionally receiving The greater 'length of thetube 3l is enclosed within a thermal insulating sleeve 3,3 to preventtransfer of heat between the outgoing and incoming coolant.

The hollow passage forming sleeve 3| has a shouldered end tting within'a similarly formed end of a sleeve 4| of electrically insulating ma.

i'ferial interposed between the sleeve 3l and the extension Z3 of thecoil support. Similarly, the arbormembers 2d and 32 are electricallyinsulated vfrom. the surrounding arbor members by an insulating sleeve42 forming an extension of the sleeve All.

The annular arbor portion it is surrounded by an outer arbor portion Q3of greater diameter which forms therewith a passage dil for quenchinghuid. The passage lf3 is continued by an outer sleeve lo threaded to thearbor portion dii and secured in position by a partially split loch nut36 having a locking bolt il for drawing the two parts of the nuttogether. An annular nozzie member it isthreaded in the end oi the innerarbor portion @t and formed so as to cooperate with the adjacent end ofthe outer sleeve to provide a quench nozzle at such an angle that thequenching iiuid is directed outwardly at an angle away from the adjacentheating coil.

rlhe construction is such that the heating head is easily replaceableupon removing two threaded connections. when the plug lil is unserer/ed,the annular ring 3G whichl is keyed thereto to-J gether with the hollowthermal insulating meinber @il can be pulled out of the head. with theplug. The hollow bolt Zi@ can then be unscrewed and removed permittingremoval of the hollow sleeve Si; This permits removal of the heatinghead comprising the coil supporting member and coil iii, the insulation(il being removed therewith.

The quench head is also readily removable for replacement by a head ofdifferent diameter. To do so, the nozzle member lil is unthreadedwhereupon the sleeve t5 can be unthreaded after first releasing theloci; nut d6. A new sleeve H35 oi different diameter and a nozzle memberlil of diiierent radial depth can then be substituted to accomodate aworkpiece 5i of diierent diameter. At the same time a heating head oithe desired diameter can be placed in position and the holding membersconsisting oi the hollow bolt 3, plug ld and associated parts can thenbe replaced and secured in position.

in order to accurately position and support the end of the outer arborportion 33, a plurality of circumferentielly spaced supporting blocksare keyed in the outer face of the inner arbor portion 26 and engage theinner face of the outer portion-43. Inasmuch as these spacers arelocated in the quenching liquid' passage, they are formed of streamlinecontour in order to avoid producing turbulence in the uid. This huid maybe either liquid or gas as described in my above mentioned application.

It will be apparent that incoming coolant iiown ing through the passagesI2, I3, lll, etc.,is protected against the heating effect of theoutgoing coolant iiow'ing through the hollow bolt. 29 and passage by thethermal insulating members above described. There is no discharge ofcoolant outside the heating head and none is brought into contact withthe surrounding workpiece.

Although I have described one embodiment only of. the invention inspecic detail, it will be apparent that the invention is not limitedthereto but can be variously modified and adapted within the scope ofthe appended claims.

What is claimed is: f

1. The'combination in an induction head for heat treating, of asupporting and current conducting arbor, a, tubular induction heatingcoil, a 'coll support including a current conducting exmeans forming acoolant conveying passage betension, meansfor electrically connectingsaid extension to said arbor including circumferentially spaced contactsmounted on said arbor and slidably engaging said extension, a hollowclamping bolt extending through said support and extension andengageable4 with said arbor for clamping said coil and support thereto,and

tween said tubular coil and said hollow bolt.

2. The combination in an induction head for heat treating, of asupporting and current conducting arbor, a tubular induction heatingcoil, a coil support including a current conducting extension, means forelectrically connecting said extension to said arbor includingcircumferentially spaced contacts mounted on said arbor and slidablyengaging said extension, a hollow clamp-l ing bolt extending throughsaid support and extension and engageable with said arbor for clampingsaid coil support thereto, means forming a coolant conveying passagebetween said tubular coil and said hollow bolt, and a tube oi thermaiinsulating material extending through said bolt to form a non-conductingwall around the coolant passage therein.

3. The combination in an induction vhead ior heat treating, of asupporting hollow `arb-or, a tubular induction heating coil, an annularcoil support, a hollow clamping bolt extending through said support andengaging said arbor tor securing said coil support to said arbor andforming with said arbor a coolant-return passage, means providing acoolant supply passage surrounding said bolt and arbor, means connectingsaid supply passage to one end of said coil, a sleeve of thermalinsulating material extending through said bolt to form a non-conductingwall around said return passagaand a' chambered member closing saidannular coil support and connecting the other end of said tubular coilto said hollow bolt, and means for connecting said insulating materialto said chambered member for removal therewith.

1i. The combination in an induction head for heat treating of a.supporting hollow arbor, e. tubular induction heating coil, an annularcoil support, a hollow clamping bolt extending through said coil supportand engaging said arbor for securing said coil support to said arbor andforming with said arbor a coolant return passage, means providing acoolant supply passage surrounding said bolt and arbor, means connectingsaid supply passage to one end of said coil, a sleeve f 'thermalinsulating material kextending through said bolt to form anon-conducting wall around Said return passage, a chambered memberclosing said annular coil support threaded to said coil support andforming a passage be- 'tween the other end of said tubular coil and saidhollowbolt, and means connecting said insulating material to saidclosure whereby removal of said closure withdraws said insulatingmaterial from said bolt.

5. In an induction heating head, an annular coil support, a currentconducting coil carried by said support and having a coolant conductingpassage therethrough, said support having axially spaced passagesextending through the wall thereof and connected with said coil passagefor conducting coolant thereto and therefrom, and circumferentiallyspaced concentric tubular memberswithin said support, said members atone end being connected together influid-tight engagement, one of saidaxially spaced passages being in communication with the space betweenthe borethereof and having a passageway through the wall thereof incommunication with the interior of the innermost of said tubularmembers, and a current conductor surrounding said support, saidconductor having a coolant conducting passageway therethrough incommunication at one end through the wall of said support with the spacebetween said members and in communication at its other end through thewall of said support with said closure member passageway.V

7. In an induction heating head, annular coi-l support, concentriccircumferentially spaced tubular members within, said support engagedtogether at one end within said support in viluidtight relation toconstitute an outer closed-end passage, 4a sleeve of thermal insulatingmaterial within the innermost of said members, said sleeve constitutingan inner open-end passage thermally insulated from said outer passage,a'closure l ember within said annular support'closingthe bore thereofand having a passageway throughthe wall thereof in communication withthe interior of said sleeve, and acurrent conductor surrounding saidsupport, said conductor having a coolant conducting passagewaytherethrough in communication at one end through the wall of saidsupport and the innermost of said members with said outer passage and'atthe other end through said support wall with said closure memberpassage.

-8. In an induction heating head, an annular support having a bore, acurrent conductor surrounding said support, means within saidsupportde'ningcconcentric outer and innerv passages, said inner passageopening at one end into the bore of said support, a sleeve of heatinsulating material. within said inner passage, a removable closuremember` for the bore of said l. support, and lmeans connecting saidsleeve and closure member for removal of said sleeve with said closuremember, saidconductor having a coolant passageway in communication atone end with said outer passage and at its other end through saidclosure member with the interior of said sleeve.

9. The combination in an induction heating apparatus, of an annularsupport, a current conductor surrounding said support and having acoolant conducting passage therethrough, concentric tubular memberscircumferentially spaced from each other, said members being connectedtogether at one end within said support in fluidtight engagement, saidpassage being in communication with the space between said members andwith the interior of the innermost of 'said members, a tubular arbor,and a conduit Within and spaced from the internal wall of said arbor,

lspace betweensaid members being in coolant condiicting communication`with the space betweenthe inner wall of vsaid arbor and said conduit.

HOWARD E. SOMES.

